A talented baseball pitcher, Peter Thompson accidentally uncovers the secret of Diana Baker, his strict English associate professor. Rigorous in campus work, Diana sings at underground bars at night to repay a $400,000 gang debt fraudulently incurred by her ex‑husband. Though Peter once blackmails her with the secret, he chooses to stand by her after witnessing her desperate plight. Allying with brilliant scholar Sophia and bold heiress Alice, he fights against the Red Moon Gang and secures debt cancellation for Diana through risky tactical negotiations. Amid numerous dangers and conflicts, precious bonds are formed. While protecting the people he cares about, Peter leads his university baseball team striving for glory in national tournaments.
